Comnet Four-Channel RS232/422/485 2&4W Bi-directional Universal Data Transceiver sm 1 - FDX4DS1A

Comnet FDX4DS1A Four-Channel Data Transceiver

Overview

The FDX4DS1A is a four-channel bi-directional data transceiver designed to transmit RS232, RS422, and 2/4-wire RS485 signals over a single-mode optical fiber at distances up to 69 km (43 miles). Each channel operates independently at data rates up to 250 Kbps, making it suited for unconditioned roadside and out-of-plant installations where electrical noise or lightning strike risk rules out copper serial links. The plug-and-play design requires no optical or electrical adjustment — power it with 8–15 VDC, terminate your data lines and fiber, and the unit is operational. Bi-color LED indicators (red/green) show received data, transmitted data, and optical carrier detect status at a glance.

Compatibility

The FDX4DS1A pairs with any equipment that outputs RS232, RS422, or RS485 signals — industrial PLCs, traffic control systems, SCADA devices, access control readers, and legacy serial instruments. Because each of the four channels is independently configurable, you can mix protocols on the same transceiver (e.g., two RS232 channels for modem control, two RS485 channels for sensor data). The unit works with both ST and FC optical connectors, so verify your fiber panel or pigtail type before ordering. The single-fiber design (using WDM or time-division multiplexing internally) means you deploy only one strand to the remote end — a cost and installation advantage over dual-fiber setups.

Installation Notes

Mount the FDX4DS1A on a wall, DIN rail (with optional DINBKT1 adapter), or in a 2-slot rack frame. Power and data connections use captive terminal blocks — strip and insert wire, no special connectors. Automatic resettable solid-state circuit protection prevents fuse nuisance trips from transient surges. Tested to NEMA TS-1/TS-2 and Caltrans traffic-equipment standards, the unit handles -40°C to +75°C operation and 0–95% non-condensing humidity. Optical power budget of 23 dB supports 69 km over 1310 nm single-mode fiber; verify your fiber loss budget if running at maximum distance. Lead times for single units may vary; confirm availability with your supplier.